Incandescent lamp



J. J. VETERE INGANDESCENT'LAMP Filed Nov. 6. 1967 May5, 197 0 JOHN J.,VETERE INVENTOR ATTORNEY Patented May 5, 1970 3,510,718 INCANDESCENTLAMP John J. Vetere, Beverly, Mass., assignor to Sylvania ElectricProducts, -Inc., a corporation of Delaware Filed Nov. 6, 1967, Ser. No.680,855 Int. Cl. H01j /48, 5/00 US. Cl. 313-318 4 Claims ABSTRACT OF THEDISCLOSURE Tungsten-halogen lamps have been previously used in theautomotive fields as accessory lamps, but recently new applications havebeen adopted. One recent use of the tungsten-halogen lamp is inautomotive headlight assemblies. Due to this new application, increasingdemands have been put on the lamp manufacturer to develop lamps andfixtures for racing vehicles. Some of the requirements demanded fixtureswith a multitude of design factors, such as, the use of scaledreflectors with various combinations of lenses. Also the lamp had tohave a singleended mechanical base with a pre-focus adaptability andprovided with a single electrical spade contact. These design variationsproduced an interchangeable lamp with the desired light output andcontrolled light patterns necessary for night racing.

Although adequate light patterns were achieved with these designs,featuring the tungsten-halogen lamp, the high temperature generated bythe lamp produced other problems. Two major problems encountered due tothis excessive heat in the base area of the lamp are: insulationbreak-down and separation of the electrical spade contact from the sidecovers. Under the condition of competitive night racing, wherecontinuous illumination is required, these problems become of primeimportance.

In the basing of a lamp with the above-mentioned specifications, certainassembly steps must be performed. A lamp of this type is provided with apress-seal with an I-shaped cross section at one end where the filamentleadin wires are directed out beyond the seal. To provide a mechanicalbase for the lamp, a pair of metal seal cover plates are utilized tocover the press-seal area. The seal covers extend below the seal andprovide a housing for an insulated spade contact and also to support analignment disc for insuring coil alignment in each fixture.

To provide an electrical connection to the lamp, one of the filamentlead-in wires is attached to the inside of a seal cover plate while theother lead-in wire is attached to the top edge of the spade contact.After this operation, the side plates are welded together over the pressseal. The aligning disc is then slid over the joined side plates and isfastened in place at a point just short of the end of the press seal.

An insulating material, usually of epoxy-resin composition, is thenplaced in the area around the contact spade, for the purposes ofseparating and insulating the spade from the side covers. After theepoxy-resin has setup or hardened, a pinch or staking operation is thenperformed to the outside of the cover plate extensions at a pointadjacent to the new potted spade, this operation pinches the side coversinto the insulation.

The above-described fabrication provided based lamps with adequatespecifications in the lower wattage range. But due to increased speedsin the racing fields, higher illumination for deeper track penetrationwas needed. When lamps of increased wattage were utilized in this field,the heat problems previously mentioned were fostered.

. Part of the heat generated by the lamp filament settled in the basearea. During continuous normal operation, when the lamp is fixed withina weather-sealed fixture, the heat build-up in the seal area graduallyweakened the holding qualities of the epoxy insulator. Thus, because ofbreak-down of the insulator the rough service to which the lamp will besubjected, short circuits sometimes 00- our between the contact spadeand the cover plates. Also, during replacement of the lamp, separationsometimes occurs between the spade and the base. These problems requiredlonger pit-stops for the racing vehicle.

I have overcome these problems by providing a lamp base with positivelocking features built around the contact spade. I also provide aninsulator for the spade that retains its workable characteristics, evenunder these high lamp operating temperatures.

Included in the construction are side covers, an alignment disc,insulator material and a spade contact. By redesigning the normally flatcontact spade so as to form an enlarged build-up ledge, an enlargedpressure area between the spade and the side covers can be made. Apreformed Teflon insulating sleeve is fitted over the spade in place ofpotting material previously used to entirely isolate the metal contactspade from the side cover. A clearance hole through the ledge and thecover plates is provided for the insertion of an insulated rivet whichwill positively hold the insulated contact spade to cover plates. Notonly does the rivet firmly hold the spade in place, but by virtue of theraised ledge, compression will be greater between the spade and thecovers.

Other features, advantages and objects of the invention will be apparentfrom the following description taken in connection with the accompanyingdrawing in which:

FIG. 1 is an exploded view of the pertinent components of the invention;FIG. 2 is an elevational view of a completed lamp and base, and FIG. 3showed another form of the contact portion of the base.

Referring to FIG. 1, a lamp assembly is shown in a pre-assembledorientation. The lamp 4 of vitreous material is provided with aconventional I-shaped press-seal base 6 having a pair of lead-in wires 8extending beyond the seal. According to the present invention, alocating node 14 has been disposed on each side of the flat surface 13of the press-seal. The node is centrally located between the raisededges 12.

To provide a mechanical spade-type base for this particular press-seal,I incorporate a pair of mating cover plates 16. Each cover plate ispre-stamped to coincide with the shape of one-half of the side of thebase 6. That is, the plates are deformed with a pair of grooves 18 thatfit over the raised edges 12 of the press-seal and extend beyond theedges terminating in Wing extensions 19. Centrally located between thegrooves 18 on each plate 16 is a horizontally elongated slot 20. Thepurpose of the slot is to receive the glass node 14 of the press-sealfor locating and holding the lamp in a prescribed coil to basearrangement. The shape of the slot 20 allows only lateral adjustment ofthe plates 16. The plates 16 extend below the groove 18 approximatelythe same distance as the length of groove 18 and are provided with innerdirected cars 22. Located on the lower part of each plate andequidistant the ears 22 is a hole 24, the purpose of which will bedescribed hereafter. Another component of the base structure is analignment disc 26 provided with a centrally located slot 28 on its topsurface. The slot is formed by displacement of the surface to form apair of upstanding ears 30 defining two long sides to the slot 28. Atpre-calculate-d positions on the top of the disc are two upstandingstuds 32 located for maintaining the lamp in an aligned operativeposition. A portion of the disc 26 is cut away to define a locating edge36, to coincide with a conventional socket.

An electrical flat spade 40 having a raised ledge 42, heavier than thebasic tong portion of the spade, the top part of the ledge is reduceddown to define a small upstanding tab 46. An orifice or clearance hole48, similar in size to the holes 24 in the side covers, is locatedthrough the ledge portion.

The above-mentioned components are the major structural parts of thebase with the exception of a Teflon fiat insulator sleeve 50, a rivet 52and a circular Teflon insulating sleeve 54. The flat sleeve 50 isutilized to isolate the spade 40 from the side cover 16 and the circularsleeve 54. -It insulates the rivet 52 from contact with the ledgeportion of the spade.

The assembly steps taken in this new improved lamp base are similar tothat previously mentioned. The upstanding ear 46 of spade 40 isconnected to one of the lead-in wires 8 by a solder or weld operationwhile the other lead-in wire is bent to a position where it contacts aside cover 16 and is also welded in place. The side covers 16 are thenfixed over the press-seal portion of the lamp and secured in place by aweld applied to the wing extensions 19. In this fixed position the sidecovers completely encompass the press-seal with the exception of thenode 14 of the press-seal which is located within the elongated slot 20.The node and slot arrangement maintains a coil-to-base relationship ofthe lamp and also locks the covers 16 to the press-seal. With the covers16 in place, the flat Teflon sleeve 50 is then slid over the raisedledge 42 of the spade 40 to completely isolate the side covers 16 fromthe spade.

Only two minor operations remain to complete the lamp assembly, one isthe attachment of the locating disc 26 over the side covers. This isaccomplished by sliding the disc 26 over the cover extensions to a pointshort of the end of the grooves 18, where the disc is firmly secured bya weld or other similar fastening means. To finish this assembly, theTeflon circular sleeve 54 is inserted through the orifices 24 in thecovers 16, through a mating hole 51 in the Teflon sleeve and hole 48 ofthe ledge 42. The rivet 52 is then passed through sleeve 54 and crimpedto firmly secure the spade 40 to the side covers 16.

In FIG. 2 a completed lamp is shown and the positions of the componentparts as described previously. In FIG. 3, a form of spade is shown whichmight be used where speed in changing the lamp is not as essential as inracing. In this, the spade 40 has the bent portion 41 for providingcontact.

It is apparent that modifications and changes may be made within thespirit and scope of the instant invention but it is our intentionhowever only, to be limited by the appended claims.

I claim:

1. An incandescent lamp base comprising: a sealed envelope of vitreousmaterial having a press-seal portion of generally I-shaped transversesection, said press-seal provided with a locating means thereon; a pairof lead-in conductors hermetically sealed through and extending beyondsaid press-seal; a pair of metal cover plates, each of whichcoincidental to the other disposed about said press seal and extendingbeyond the lower end thereof; said cover plates fitting over saidlocating means; alignment means disposed about said cover plates andattached thereto; a conductive metal spade disposed within the lowerportion of said seal plates and attached to one of said lead-inconductors; a raised ledge disposed on said spade and within said coverplates; insulating means disposed about said spade between said coverplates and said spade; locking means positioned through said coverplates and said raised ledge of said spade to firmly hold the spade andcover plates in a fixed position.

2. The lamp according to claim 1 wherein said alignment means is a disc.

3. The lamp according to claim 2 wherein said pressseal portion is ofI-shaped transverse section.

4. The lamp according to claim 2 wherein said lamp envelope contains aniodine fill.

References Cited UNITED STATES PATENTS JOHN W. HUCKERT, Primary ExaminerA. I. JAMES, Assistant Examiner U.S. Cl. X.R. 313-317, 331

